If we can have fuses in the engine compartment or baggage compartment then location must not be important.  What is important is to remember why we put circuit breakers in the circuit, and that is to protect the wire, not the device at the end of the circuit.  In order to do that you want the circuit breaker as close to the beginning of the wire (circuit) as possible which means near or at the master buss.  In your proposed configuration, you will have protected the pump motor, but if you get a short in the wire back to the master buss there is nothing to break that circuit and you could have a fire.  Something to think about.

 

Good luck

 

Cliff Scheel

ES-P builder